Neurodevelopmental outcomes of infants evaluated for but not treated with therapeutic hypothermia: a prospective cohort study
Mohamed El-Dib1,2, Danielle Sharon3, Elizabeth Singh3
1Division of Newborn Medicine, Department of Pediatrics, Brigham and Women's Hospital, Boston, MA, USA. mel-dib@bwh.harvard.edu.
Background:
Therapeutic hypothermia (TH) is the standard of care for moderate to severe neonatal encephalopathy (NE). Although some centers consider TH for mild NE, neurodevelopmental outcomes of infants who do not meet eligibility criteria are incompletely defined.
Methods:
Infants evaluated for TH based on perinatal risk factors, but who did not meet institutional eligibility criteria, were prospectively enrolled. Neurodevelopmental outcomes were assessed at 24 months. Bayley-4 scores <85 were classified as sub-normative performance.
Results:
Of 39 infants enrolled, 26 completed Bayley-4 assessments. Thirteen (50%) demonstrated sub-normative performance in at least one developmental domain; only one of them had an acute brain injury on MRI. Compared with infants with average-range performance, those with sub-normative performance had higher postnatal base deficits (10.1 vs 6 mmol/L, p 0.04), higher postnatal lactate levels (9.4 vs 4.9 mmol/L, p 0.05), and a trend toward less sleep-wake cycling on aEEG (45% vs 83%, p 0.06).
Conclusions:
A substantial proportion of infants evaluated for but not treated with TH demonstrated sub-normative developmental performance at 2 years. Absence of acute MRI-detected injury does not preclude later developmental vulnerability. These findings support longitudinal follow-up of infants who are evaluated for TH but do not meet TH criteria.
Impact:
Infants evaluated for but not treated with therapeutic hypothermia demonstrated a measurable risk of neurodevelopmental vulnerability at 2 years, with 50% demonstrating sub-normative performance (>1 SD below the normative mean) in at least one domain on the Bayley Scales of Infant and Toddler Development Fourth Edition. Early postnatal metabolic abnormalities in infants evaluated for therapeutic hypothermia showed a potential association with later developmental outcomes. There is a need for improved risk stratification and structured longitudinal follow-up for infants evaluated for but who do not meet cooling criteria.
